Comprehensive Description

Description

“Parepimeria major,n.sp.

Occurrence: St. 177. South Shetlands. One specimen 17 mm.

Description. In general habitus like crenulata var. miothele. Head carinate, with short deflexed rostrum. Eyes broadly oval, quite white as preserved. A sinuous oblique ridge from upper hind margin of eye to middle of hind margin of head. Peraeon segments 1-4 rounded dorsally; I with a transverse groove, 2-4 each with the posterior margin gibbous; segments 5-7 each with a pair of long acute processes; no tubercles on lower margins of segments. Side-plate I acutely produced forwards; 2 and 3 ovate, subacute below; lower hind margin of 4 concave. Pleon segments I and 2 each with a strong projecting acute medio-dorsal tooth; segment 3 with a rounded keel posteriorly; postero-inferior angle of segment 1 quadrate, of z shortly pointed, of 3 quadrate with a short tooth; lateral margins of segments 1 and z slightly angular, of 3 with a small upturned tooth. Telson short, broad, apically rounded, dorsally concave, lateral margins raised, with a spine a little beyond the middle.

Antennae and mouth-parts as in crenulata. Pa1p of maxilliped with a strong spini­form 4th joint surrounded by the numerous setae of the 3rd joint.

Gnathopods 1 and 2 stouter than in crenulata, no regular row of spinules on hind margin of 2nd joint, but a few distally, 5th joint strong, broadly expanded, 6th also broader than in crenulata. Peraeopods 3-5, 2nd joint oblong, successively more ex­panded on hind margin proximally, hind margin very obscurely serrulate, a longitudinal keel from base to apex and an oblique one antero-proximally.

Remarks. Unlike the form described above as var. miothele, this form does not labour under the suspicion of being a variety of crenulata. The gnathopods are much stronger, and bear a remarkable resemblance to those of Melphidippa macrura. The specimen shows no sign of either penes or developing brood lamellae, and is thus immature. The adult must be considerably larger than crenulata.”